Counter flow still



maa ses Jan 10, 1928.

F. r E. GIILMORE COUNTER FLOW STILL more mm EPW013395 E Filed AprilPatented Jan. 10, 1928.

UNITED STATES PATENT OFFICE.

COUNTER FLOW STILL.

Application filed April, 23, 1925. Serial lie. 25,274.

My invention relates to a still for refining mineral oil and itsproducts.

It is an object of this invention to provide a still which may be usedas a skimming still a for use in a refinery to extract gasoline fromcrude .oil, also as a cracking or converting still, in which case it maybe used either singly or connected in series; it may also be used as astill in conjunction with an absorpto tion gasoline plant to distillgasoline from the saturated absorption medium.

With the-above and, other objects in view which will appear as thedescription proceeds, In invention consists in the construction anarrangement of parts hereinafter described and claimed.

In the accompanying drawing, which forms a part of this specification,

Figure 1 is a vertical crosssection of a still embodying my invention.

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1.

Fig. 3 is a horizontal section taken on the line 33 of Fi 1, and

Fig. 4 is a etail view in vertical cross section, showing thearrangement of the heating tubes. v

' Referring to the drawings, 1 represents the shell of a vertical stillclosed at the bottom and top and which is shown in Fig. 2 as rectangularin cross section, 2 representing the front and rear sides, and 3 thesides of the shell 1.

In the lower portion of the shell 1 there.

are arranged in spaced relation a plurality of groups of heating pipeshorizontally dis osed and having their open ends arranged 1n the sidewalls 3 of the shell 1 and designated as 4-,,5, 6, 7 and 8,respectively, group 4 being near the bottom of t e shell 1. Hot gasesirom'a furnace or dutch oven (not shown) communicate by means of aconduit 9 with the lowermost group 4 of the heating ipes. The side walls3 are provided with ues 10 which conduct the hot gases from one group ofheating pipes to the group immediately above, so that the hot gases passsuccessively through the groups of heating pipes 4, 5, 6, 7 and 8, andfrom thelatter they pass through a smoke stack 11.

Near the top of the shell 1 is a valve-controlled vapor outlet 12,leading to a condensor, not shown. Some distance below the vapor outlet12 is a temperature regulator 13 com rising a thermocouple, whichcontrols va ve 14. in the cold oil inlet pipe 15.

In the upper part of the shell 1, above the grou s of heating pipes,there are a series of so-ca led bubbler trays, horizontally disposed.Each bubbler tray consists of a pan 16 having a rim 17, from which theliquid falls onto a circular distributor 18, whence the liquid fallsonto a tray 19, from whence the liquid falls through a centraldownwardly extending pipe 20 which terminates a short distance above thebottom of the pan 16,- thus forming a liquid seal.

An inlet: 20 of hot oil enters the still at the point between the thirdand fourth bubbler trays. In the space above the bubbler trays finebattling material 21 is disposed for the extraction of mists. The spacebetween the grou of heating pipes 4, 5, 6, 7 and 8 is filled w thbafiling material, shown in the present instance as expanded metal lath22, although similar material may be substitutedtherefor. The spacebetween the lowermost group of heating tubes 4 and the bottom of thestill constitute an oil collecting chamber 23, from which an outlet pipe24, controlled by a constant level valve mechanism 25, leads to a heatexchanger, or the'like.

As shown in Fig. 4, the heating pipes are preferably arranged instaggered relation and they may be cleaned of any deposits of carbon andthe like by removing manhole covers 26 arranged in the front and rearwalls of shell 1. I

In the operation hot oil is introduced through the inlet 20 into thestill. Some cold oil is also introduced through the cold oil inlet 15into the still, the amount of the cold oil being regulated by thetemperature regulator 13. The cold oil lowers the temperature of therising vapors and scrubs them in such a way that all the heavy fractionsin the vapors which are not desired in the finished product arecondensed and returned to the still below. The hot oil passingdownwardly from one bubbler tray to another falls over the top group ofheating pipes 8 and successively downwardly over the other groups 7, 6,5 and 4, until it reaches the oil collectin chamber 23, whence it passesout through t e outlet24. As the group of tubes 4 near the bottom of thestill are very hot and the groups of tubes 5, 6,

7' and 8 above the first lowermost group are successively of a lowertemperature, the oil falling downwardly from one group to another ofsaid heating tubes has its temperature successively raised. As a resultthere is a slight amount of cracking and each fraction of the 011 givenoff or evaporated at the lowest tem erature-at which it will pressure atwhich the thene series with the result that the product is an anti-knockfuel. Since the gases from the furnace have a counter-flow action withtheoil, the fuel economy is very great. The

'bubbler trays'acting as a fractional eondenser make it possible to geta finished gasoline or motor fuel without the necessity of re-running itin a steam still.

hen the still is used as a cracking or converting still, the tem eratureat the bottom of the still will be a out 800 or 900 F., and there may besome coke'formed by this high heat which may be cleaned off by removingthe manhole' covers 26, as above stated.

The important part of the still is the counter-flow action, whereby thedescending oil passes successively over a set-of heating tubes, eachsucceeding tube being hotter than condensate in the the one before. Alsoany b h y-gravlty to t e bubbler trays is returne hot tubes. Thebafiling material 21 and 22 increase the surface for the evaporation ofthe oil.

The still may also be used in an absorption plant, in which case the oillevel may be held above the top of the lowest set 4 of the heatingtubes.

Thus I have designed a still, simple of construction, and efficient andeconomical in operation, which may be used as a skimming still, or acracking or converting still, or a still for distilling off gasolinefrom absorption medium.

While I have shown the preferred form of construction of the still, itis to be understood by those skilled in the art that various changes inthe construction and arrangement of parts may be made without departingfrom the spirit of the invention, as claimed.

I claim:

A still for use in refining oil, comprising a vertical shell rectangularin cross section, a plurality of sets of heating pipes horizontallydisposed in vertical spared relation in said shell, bathing materialdisposed between said sets of heating pipes, a hot gas inlet to thelowermost set of heating pipes, means for passing gases successivelythrough the sets of heating pipes disposed above said lower set, aseries ofbubbler trays disposed in the upper part of said shell,battling material above said bubbler trays, a vapor exit from the upperpart of the shell, a hot oil inlet entering the shell between saidbubbh-r trays, a cold oil inlet above said hot oil inlet, a thermostaticcontrol for the cold oil inlet, and a float controlled oil outlet nearthe bottom of the shell.

In testimony whereof I have signed my name to this s cification.

ORREST E. GILMORE.

